The present invention relates to an applicator used for the application of various kinds of liquids, e.g. paint, liquid adhesive, and the like and more specifically to a roller for applying and spreading such liquids onto a desired surface. The invention also relates to a device with an applicator for applying paint to the wall face of a building, a steel-frame bridge, and the like.
Known roller systems for applying and spreading liquids have a rotatable application roller mounted to a pipe which introduces to the roller attached thereto the liquid to be applied. The pipe is connected to a liquid feeding pump. A plurality of effluent holes for the liquid to be applied are uniformly spaced around the pipe which is located at the inside of applicator roller. The liquid percolates out of these effluent holes from the internal surface side of the applicator roller to the outside. However, such a conventional applicator roller causes the liquid on the surface of the applicator roller to be gradient widthwise so that a non-uniform painting is easily incurred because the nearer the above-mentioned effluent hole is to the side where the liquid is introduced from the pipe, the more easily it flows because of higher pressure at those effluent holes. Furthermore, if the viscosity of the liquid to be applied is low, drops thereof come out in the vicinity of the above-mentioned introduction side, causing the surroundings become dirty. In this regard, if the feeding pressure of liquid is decreased to avoid such a situation, a blurred spreading takes place on the portion remote from the introduction side. For this reason, it is extremely difficult to adjust the discharge amount by a modification of the liquid feeding pressure. In addition to that, a problem is incurred when the feeding of the liquid is stopped because the liquid which remains in the inside of the applicator roller and in the introduction pipe drips out when the applicator roller is inclined.